Chrome: Gmail has tons ofgreat shortcuts, but they're only as good as how often you remember to use them. Shortcuts for Gmail is a Chrome extension that will let you know every time you do something that you could have done with a shortcut by displaying the shortcut on-screen. With luck, you'll remember it for next time.

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Shortcuts for Gmail is much like previously mentionedEve, a Mac app that does the same in the OS. Every time you perform an action for which there's a Gmail shortcut, a pop-up alert like the ones in the image above will appear in the lower-right corner of your Chrome window, letting you know how you can do the same thing without taking your hands off the keyboard. You'll have to have shortcuts enabled in Gmail (under general settings and "keyboard shortcuts") for Shortcuts for Gmail to work.

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The extension is available now in the Chrome Web Store, and it's from an validated publisher, but be warned: the permissions it needs to work are pretty hefty (although they make some sense) so that may put some people off of it. If you'd rather learn the hard way, remember you can always press "?" in any Gmail window to bring up an overlay with every Gmail shortcut listed in it.